1. Field of the Invention
The present invention relates generally to the field of wireless communication systems and more particularly to wireless communication systems and methods for automatically providing updated location estimates for wireless communication devices to emergency services providers during emergency calls.
2. Description of the Related Art
A person desiring emergency services in most areas of North America may place an emergency call to an appropriate emergency services provider (e.g., a governmental public safety organization responsible for the provision of such services) by dialing the digits “911” on a wired or wireless communication device. The emergency call is then routed and connected to a dispatcher located at a public safety answering point of the emergency services provider. Soon after communicating certain basic information to the dispatcher, the person (i.e., the caller) generally receives emergency services from police, fire, or paramedic personnel as appropriate.
When such an emergency call is made by a caller using a wireless communication device, the caller's wireless service provider must also provide certain data to the emergency services provider. The required data is specified by governmental regulations pertaining to the handling of emergency calls originating from a wireless telephone or other wireless communication device. The governmental regulations are commonly referred to as “e911” regulations and currently include two sets, or phases, of regulations. For the wireless service provider's network to be compliant with the first phase of the e911 regulations pertaining to such calls (e.g., the Phase I e911 regulations), the wireless service provider must provide the telephone number of the caller's wireless communication device and the street address of the cell tower providing service to the caller's wireless communication device. Alternatively, for the wireless service provider's network to be compliant with the second phase of the e911 regulations pertaining to such calls (e.g., the Phase II e911 regulations), the wireless service provider must provide the latitude and longitude corresponding to a location estimate for the caller's wireless communication device in addition to the information or data provided in accordance with the Phase I e911 regulations.
According to the Phase II e911 regulations, the wireless service provider's network generally provides an initial location estimate (including, but not limited to, the latitude and longitude of the location estimate for the caller's wireless communication device) to the public safety answering point of the emergency services provider upon request therefrom once a voice communication path is established for the emergency call. Subsequently, the dispatcher at the public safety answering point may optionally request updated location estimates for the caller's wireless communication device during the emergency call, but the wireless service provider's network provides such updated location estimates only in response to such “pull” requests.
The ability to issue such “pull” requests to the caller's wireless service provider and to obtain corresponding updated location estimates is extremely important to the dispatcher in those situations where the caller is not substantially stationary. However, in many cases, the dispatcher may not know that the caller is moving until a “pull” request for an updated location estimate is made and the wireless service provider's network provides an updated location estimate indicating that the caller's wireless communication device has moved from the latitude and longitude associated with the initial location estimate. In those cases where the dispatcher knows that the caller is moving, the dispatcher may not know how fast the caller is moving and, as a consequence, does not know how frequently to request updated location estimates. If the dispatcher requests updated location estimates too frequently, the wireless network resources required to provide such estimates may be unnecessarily tied up. Alternatively, if the dispatcher requests updated location estimates too infrequently, the dispatcher may not know the location of the caller's wireless communication device with any reasonable degree of certainty and, hence, cannot accurately direct public safety personnel to the caller's current location. To further aggravate these difficulties, there is always a chance that an updated location estimate may not be as accurate as the initial location estimate.
Notably, in the majority of emergency call situations, the caller making the emergency call is stationary or substantially stationary. As a consequence, the provision of updated location estimates in such situations in response to dispatcher “pull” requests is unnecessary and prevents valuable wireless communication network resources from being utilized for other purposes.
Therefore, there exists within the industry a need for wireless communication system and methods for providing an emergency services provider with updated location estimates for a caller's wireless communication device during an emergency call that addresses these and other problems or difficulties that exist now or in the future.